Just one year ago, Anthony Powell – who will be running his 78th marathon on Sunday – received the most devastating news any parent can get.

Doctors said his 15-year-old daughter Natasha Powell had stage four Hodgkin lymphoma. The cancer had spread to her spleen, neck, stomach, lymph nodes, groin and chest.

She had been a normal, healthy teenager until she started to feel unwell and found a lump in her neck.

Natasha was immediately admitted to the specialist Teenage Cancer Trust Unit at the University Hospital of Wales in Cardiff for intensive chemotherapy. After seven months of treatment, Natasha was discharged and is currently in remission.

Anthony Powell with his daughter Natasha Powell

Anthony, 47, said: “From the second Natasha arrived at the Teenage Cancer Trust Unit, she was cared for and supported every step of the way.

“The staff were fantastic and explained everything that was going to happen. Natasha received the most incredible support and, as a family, we are so grateful to the charity for providing the care for Natasha throughout her cancer treatment.

Seven young people are diagnosed every day

“I am running the marathon this time to help make a difference to other young people with cancer and give something back to Teenage Cancer Trust. My aim is beat my personal best of 2:52.33 and raise £500 for the charity.”

The Teenage Cancer Trust said that every day around seven young people aged between 13 and 24 are diagnosed with cancer in the UK.

Traditionally treated alongside children or elderly patients at the end of their lives, they can feel extremely isolated. Being treated alongside others their own age in a Teenage Cancer Trust Unit can make a huge difference to their whole experience.

The state-of-the-art units are designed to feel like a home from home, where young people feel comfortable. The walls are bright, the furniture is funky, there are pool tables, a jukebox and a place to watch films and surf the net.

“If she can get through each and every day with four injections, dealing with low blood sugar levels, high blood sugar levels, feeling like rubbish, sore fingers due to four finger pricks daily to check blood sugar levels, painful injection sites, only to name a few of the daily challenges ...then I can sure as hell drag my backside around 26.2 miles.”

Watching her daughter Gwen Richards, 15, cope with diabetes Type 1 since the age of seven has made Lindsey Wegner , from Ewenny, determined to complete the London Marathon and raise money for the Juvenile Diabetes Research Foundation (JDRF).

'Our whole world turned upside down'

“I’m raising money for JDRF to fund the vital research that is going on right now to figure out how to cure and prevent childhood diabetes,” said the 38-year-old, who is a business support manager for a print and design company.

“On October 2, 2007, four days before her seventh birthday, Gwen was diagnosed with Type 1 diabetes. Our whole world turned upside down.

“From day one, Gwen took control and did her own four daily injections. Never cried, never got angry, never questioned ‘Why me?’

“And almost nine years later we are all still adjusting, but Gwen continues to live her life to the max, never allowing diabetes to get in the way,” said Lindsey, who also lives with partner Simon Richards and daughter Ava Richards, six.

'Gwen's courage and strength blows us away'

She added that last year Gwen was hospitalised twice due to complications with her diabetes.

“But she still continues to get on, with a smile on her face, with a courage and a strength that blows us away.”

Lindsey said she does not class herself as a runner, having taken up the sport just three years ago to lose weight.

“I entered the 5K Race for Life which led to a 10K Race for Life raising money for Cancer Research as my mum was diagnosed with cancer around that time, and then the Swansea and Cardiff half marathons last year.

“My dad ran the London Marathon in 1984, and this seemed to be the next step for me seeing as I’d caught the running bug!”